利多卡因对微栓栓塞致大鼠学习记忆和胆碱能系统损害的影响

Effects of lidocaine on impairment of learning and memory function and cholinergic system caused by cerebral microsphere embolism in rats

目的观察利多卡因对脑部微栓栓塞致大鼠学习记忆和胆碱能系统损害的影响。方法雄性Wister大鼠随机分为(1)对照组;(2)600微栓组和900微栓组,分别经右侧颈内动脉注射600和900个微球;(3)600保护组和900保护组,分别经右侧颈内动脉注射600和900个微球,并给予利多卡因。第7天起进行水迷宫测试。最后取脑组织测定胆碱乙酰转移酶、胆碱酯酶活性和M受体结合活性。结果(1)潜伏期900微栓组明显长于对照组和600微栓组。(2)有效搜索策略百分比两个微栓组明显低于对照组;两个保护组则明显高于相应的微栓组。(3)胆碱乙酰转移酶活性皮层区域900微栓组和两个保护组均明显低于对照组,两个保护组还明显低于相应的微栓组;纹状体区域各微栓和保护组均明显低于对照组。(4)胆碱酯酶活性皮层区域900微栓组明显低于对照组和600微栓组,900保护组则明显高于900微栓组;海马区域各微栓和保护组均明显低于对照组。(5)M受体结合活性皮层区域900微栓组和两个保护组均明显低于对照组,两个保护组还明显低于相应的微栓组;海马和纹状体区域各微栓和保护组均明显低于对照组,两个保护组还明显低于相应的微栓组。结论脑部微栓栓塞产生数量相关的大鼠学习记忆和中枢胆碱能系统损害。利多卡因减轻微栓栓塞所造成的学习记忆能障碍,对中枢胆碱能系统指标有进一步抑制作用。

Objective： To investigate the effects of lidocaine on impairment of learning and memory function and cholinergic system caused by cerebral microsphere embolism in rats. Methods： Healthy male Wister rats were randomly divided into the following groups. （ 1 ） Control group. （2） 600 microsphere group and 900 microsphere group, in which 600 or 900 microspheres were injected into the fight internal carotid artery, respectively. （3） 600 treatment group and 900 treatment group, in which 600 or 900 microspheres were injected into the right internal carotid artery, respectively, and lidocaine was given. Water maze tasks were tested for 5 consecutive days from the 7th postoperative day. The rats were then decapitated and regions of cerebral cortex, hippocampus, and striatum were selected. The activities of choline acetyhransferase and cholinesterase and the binding activity of muscarinic receptor were deter- mined. Results： （ 1 ） The latency periods were significantly longer in the 900 microsphere group than in the control group and in the 600 microsphere group. （2） The percentages of effective search strategy were significantly lower in the 600 and 900 microsphere groups than in the control group. They were significantly higher in the 600 and 900 treatment groups than in the corresponding microsphere groups. （3） The activities of choline acetyhransferase of cerebral cortex were significantly lower in the 900 microsphere and two treatment groups than in the control group. They were also significantly lower in the 600 and 900 treatment groups than in the corresponding microsphere groups. Those of striatum were all significantly lower in the microsphere and treatment groups than in the control group. （4） The activities of cholinesterase of cerebral cortex were significantly lower in the 900 microsphere group than in the control and 600 microsphere groups. They were significantly higher in the 900 treatment group than in the 900 microsphere group. Those of hippocampus were all significantly lower in the microsphere and treatment groups than in the control group. （5） The binding activities of muscarinic receptor of cerebral cortex were significantly lower in the 900 microsphere and two treatment groups than in the control group. They were also significantly lower in the two treatment groups than in the corresponding microsphere groups. Those of hippocampus and striatum were all significantly lower in the microsphere and treatment groups then in the control group. They were also significantly lower in the 600 or 900 treatment group than in the corresponding microsphere group. Conclusion： Cerebral microsphere embolism caused significant and quantity-dependent impairment of learning and memory function and cholinergic system in rats. Lidocaine alleviated learning and memory dysfunction caused by cerebral microsphere embolism, but further inhibited the parameters of central cholinergic system.